"I don’t know how to touch God to feel his presence, but once you feel it, you can be sure that he exists."

The problem is: you still can't be sure. Because people in other religions also have experiences that make them "sure" that their god/religion is the right one. Through meditation someone might tell you they are sure that impermanence is the only truth. Or a muslim through their regular prayer might be sure that Allah is God and Mohammed is his messenger. Are they correct, too?